III MEF Support Battalion

Who we are

III Marine Expeditionary Force (MEF) Support Battalion provides and coordinates direct combat service support (CSS), security, and administrative services to III Marine Expeditionary Force (MEF), 3d Marine Expeditionary Brigade (MEB), and III MEF Information Group (MIG) Command Elements (CE) in order to enable III MEF to win in competition and conflict.

Featured News

3/12 Executes HIMARS Dry-Fire Training at Camp Fuji

COMBINED ARMS TRAINING CENTER, CAMP FUJI, Japan – U.S. Marines with 3d Battalion, 12th Marine Regiment, 3d Marine Division conducted High Mobility Artillery Rocket System (HIMARS) dry-fire training at Combined Arms Training Center (CATC) Camp Fuji from June 11-13, 2025. This training represents a significant enhancement of Camp Fuji’s capability to support long-range fires and reflects our commitment to maintaining readiness and deterrence in the Indo-Pacific alongside our Japanese partners.

3d Radio Battalion Change of Command

MARINE CORPS BASE HAWAII, Hawaii - On 18 June 2025, 3d Radio Battalion bid fair winds and following seas to Lieutenant Colonel Gary A. Keefer, and welcomed Lieutenant Colonel Sean F. X. Barrett to the family. Lieutenant Colonel Keefer was the Battalion Commander of 3d Radio Battalion for three years and will be retiring after 23 years of faithful service. Lieutenant Colonel Barrett is assuming command of 3d Radio Battalion after serving consecutive assignments at I Marine Expeditionary Force G-2.

Space Force Supports III MEF with Tactical Space Integration

OKINAWA, Japan- U.S. Space Force Maj. Ben Pearce and Capt. Hannah Garcia-Park, both with Mission Delta-11 (Space Ranges, Aggressors, Tactics and Exercises), conducted tactical level space operations for the first time in history June 9, 2025, at III Marine Expeditionary Force (III MEF), Okinawa, Japan. The Guardians injected critical tactical subject matter expertise directly supporting III MEF's mission, while also delivering realistic and challenging space aggressor training enhancing the lethality and combat power of the entire joint force.